Generally, a touch screen panel is an input device that allows a user to input commands by selecting instruction contents on a screen of an image display device through the use of hand or object.
For this, the touch screen panel is provided on a front face of the image display device, wherein the touch screen panel converts a contact location being in direct contact with the user's hand or object into electrical signals. Thus, the instruction contents selected at the contact location may be accepted as an input signal.
The touch screen panel can replace a separate input device, which is operated while being connected with the image display device, for example, keyboard and mouse, whereby an application field of the touch screen panel expands gradually.
A method for realizing the touch screen panel may be classified into a resistive type, capacitive type, and electro-magnetic type. Among the above, two of the most typical types may be the resistive type and capacitive type.
The touch screen panel of resistive type is formed of two substrates coated with transparent electrode. When the touch screen panel of resistive type is touched (or pressed) by the use of finger or pen, corresponding portions of the two substrates being at the touch point are attached to each other, to thereby detect the location of the touch. However, an application field of the resistive type has been reduced due to disadvantages such as difficulty of operation and inaccuracy in detecting the location of the touch.
In case of the capacitive type, when a human's hand or an object is touched thereon, a signal sensing pattern senses a change of capacitance by other signal sensing patterns or grounding electrode, whereby the location of the touch is changed into an electrical signal. That is, it uses a principle of sensing static electricity of human body. This capacitive type touch screen panel has good durability, good transmittance, and rapid response time. Recently, the capacitive type touch screen panel has been widely used.
In case of the capacitive type touch screen panel, the signal sensing patterns for sensing the location of the touch, for example, a location touched by a user's finger occupy the most of screen; and a wired electrode for transmitting the touch signal sensed by the signal sensing patterns to an external driving circuit for driving electronic equipment with the touch screen panel is positioned in the margin of screen.
However, a wired electrode of touch screen panel according to the related art has the following problems, which will be explained with reference to FIG. 1 (FIG. 1 illustrates a wired electrode of touch screen panel according to the related art).
As shown in FIG. 1, the related art touch screen panel includes signal sensing patterns 1 and 2 for sensing a user's touch signal, and wired electrodes 10, 30 and 50 for transmitting the sensed touch signal to an external driving circuit (not shown), wherein the signal sensing patterns 1 and 2 are provided in the center of substrate 100. In more detail, the wired electrodes are formed of a contact part 10 connected with the signal sensing patterns 1 and 2, a bonding part 50 electrically connected with the external driving circuit, and a signal transmitting part 30 for connecting the contact part 10 and bonding part 50 with each other. The wired electrodes enable to transmit electrical signals by forming a groove in the substrate 100 and filling the groove with a conductive material.
In this case, in order to form the groove in the substrate 100, a demolding process is carried out by the use of embossing mold whose shape corresponds to the groove. In case of the related art, the signal transmitting part 30 of the wired electrode is provided with a folded portion 11. Also, an embossing portion corresponding to the folded portion 11 is provided in the embossing mold for the demolding process. This embossing portion of the mold may be broken during the demolding process.
Also, since the wired electrode is formed by filling the simple-shaped groove with the conductive material, the filled conductive material may be easily separated during a process for manufacturing the touch screen panel. In this case, the touch signal sensed by the signal sensing patterns 1 and 2 is not transmitted to the external driving circuit.